We present here the first profiles of acetate and formate concentrations in Antarctic ice for time periods that include the great climatic changes of the past. Data are from two Antarctic deep ice cores recovered on the central East Antarctic Plateau (EDC) and in the Dronning Maud Land (EDML) facing the Atlantic Ocean (European EPICA Project). Except the sporadic arrival of diluted continental plumes during glacial extrema, the main source of acetate deposited over the EDC does not seem to have changed significantly over the past 300 kyr and is related to marine biogenic activity. A more detailed study of the past 55 kyr leads to the conclusion that acetate reaching the EDML during a large part of the last glacial maximum was emitted by the Patagonian continental biomass and was uptaken along with nitric acid at the surface of mineral dust. Changes in formate concentrations are characterised by less scattered and lower values at both sites during glacial periods. We propose that the present marine source of formic acid (Legrand et al., 2004) drastically decreased but did not completely vanish under cold climate conditions, whereas the share of methane oxidation in formic acid production became prominent.Keywords: ice cores; polar atmosphere; formic acid; acetic acid; climatic cycles(Published: 5 March 2012)Citation: Tellus B 2012, 64, 17331, DOI: 10.3402/tellusb.v64i0.17331

Preiss, N., Melie` res, M.-A. and Pourchet, M. 1996. A compilation of data on lead 210 concentrations in surface air and fluxes at the air-surface and water-sediment interfaces. J. Geophys. Res. 101(D22), 28847 28862.

Preiss, N., Melie` res, M.-A. and Pourchet, M. 1996. A compilation of data on lead 210 concentrations in surface air and fluxes at the air-surface and water-sediment interfaces. J. Geophys. Res. 101(D22), 28847 28862.